Coarse Collagen Fibers Research Articles

The dinosaurs that weren't: osteohistology supports giant ichthyosaur affinity of enigmatic large bone segments from the European Rhaetian.

Very large unidentified elongate and rounded fossil bone segments of uncertain origin recovered from different Rhaetian (Late Triassic) fossil localities across Europe have been puzzling the paleontological community since the second half of the 19th century. Different hypotheses have been proposed regarding the nature of these fossils: (1) giant amphibian bones, (2) dinosaurian or other archosaurian long bone shafts, and (3) giant ichthyosaurian jaw bone segments. We call the latter proposal the 'Giant Ichthyosaur Hypothesis' and test it using bone histology. In presumable ichthyosaur specimens from SW England (Lilstock), France (Autun), and indeterminate cortical fragments from Germany (Bonenburg), we found a combination of shared histological features in the periosteal cortex: an unusual woven-parallel complex of strictly longitudinal primary osteons set in a novel woven-fibered matrix type with intrinsic coarse collagen fibers (IFM), and a distinctive pattern of Haversian substitution in which secondary osteons often form within primary ones. The splenial and surangular of the holotype of the giant ichthyosaur Shastasaurus sikanniensis from Canada were sampled for comparison. The results of the sampling indicate a common osteohistology with the European specimens. A broad histological comparison is provided to reject alternative taxonomic affinities aside from ichthyosaurs of the very large bone segment. Most importantly, we highlight the occurrence of shared peculiar osteogenic processes in Late Triassic giant ichthyosaurs, reflecting special ossification strategies enabling fast growth and achievement of giant size and/or related to biomechanical properties akin to ossified tendons.

Patho-histological features of fibroblastic sarcoid in horses

Sarcoid is one of the most common skin tumours, which is diagnosed in various breeds of horses at any age regardless of the animal’s sex. Such fibroblastic neoplasm manifests itself in several clinical ways with its specific morphological features. As a rule, it metastasizes rarely but can be locally invasive. The disease’setiology is multifactorial and includes the confirmed role of the bovine papillomavirus and genetic and environmental factors. The article introduces the results of a retrospective study of horses of the Ukrainian riding breed with a fibroblastic sarcoid type, which was localized mainly in the area of the external thoracic vein. Neoplasms were represented by two types. The first one included broad base neoplasms without a pronounced pedicle but with signs of hyperkeratosis. Massive rounded dense formations with an ulcerated surface refer to the second type. To verify the studied types of sarcoid, wide surgical excision of the lesion’svisible parts was performed, followed by the selection of fragments for the pathohistological diagnosis. Also, additional staining methods were used to detect the connective and muscle tissue (Van Gieson’s staining) and elastic fibers (Weigert’s resorcin-fuchsin staining). Microscopically, the neoplasm without a visible pedicle showed signs of hyperkeratosis and acanthosis in the peritumoral epidermal layer. Epidermis desquamation with a significant amount of oxyphilic detritus, diapedesis hemorrhages, and dilated vessels was also detected in some areas. Chaotic placement of fibroblasts and fibrocytes was noted, to a greater extent, subdermally. Anisocytosis and anisokaryosis were expressed moderately. Sarcoids, macroscopically presented in the form of massive dense formations with an ulcerated surface, were histologically characterized by the replacement of the epidermis with cellular elements, subdermal hemorrhages, and the characteristic perpendicular orientation of coarse collagen fibers towards the basement membrane. Closely spaced spindle-shaped cells with fibers forming moiré structures were visualized in the deep dermis layers. Nuclei were hyperchromic and elongated in shape, no atypical mitoses were noted. Pathohistological examination during the identification of a sarcoid type for diagnostic purposes can cause rapid growth and formation of an ulcer. The final diagnosis regarding equine sarcoid can be made based on a combination of clinical signs, histopathological examination, and molecular genetic testing with the isolation of BPV DNA.

EXPERIMENTAL AND CLINICAL JUSTIFICATION OF THE USE OF COLLAGEN-FIBRIN ADHESIVE COMPOSITION FOR CLOSING A COLON DEFECT

Relevance: The aim of our study was to assess the degree of penetration of the intestinal area by connective tissue when using a collagen plate in rats with a colon defect. Increasing the efficiency of surgical treatment of pararectal fistulas.
 An experimental morphological study was carried out on laboratory rats of the Wistar line, which were divided into two groups consisting of 20 animals each, depending on the method of closure of the intestinal wall defect: group 1 main and group 2 comparison.
 The average weight of animals in each group was 180 ± 220 g.
 For the purpose of anesthesia, a sodium thiopental solution was used, which was prepared as follows: 1 g of sodium thiopental was diluted in 20 ml of 0.9% sodium chloride solution. Each animal was injected with 0.7 ml of a 0.5% solution.
 In the main group, the operation of closing the defect of the intestinal wall was carried out using a collagen-fibrin adhesive composition. In the comparison group, the operation of closing the defect of the intestinal wall was performed with interrupted sutures.
 At the end of the experiment, the animals were euthanized in equal numbers from each group, subject to the conditions of euthanasia, 10, 30, 60 days after surgery.
 As a result of the experimental study, the animals of the main group and the comparison group were all alive on day 10 after surgery.
 Morphological changes in histological samples of the large intestine with the closure of the intestinal wall defect with a collagen-fibrin adhesive composition consisted in pronounced leuko-lymphocytic cell infiltration. Individual infiltrates were observed that formed lymphoid follicles.
 An objective assessment of the immunohistological analysis of the samples of the operated intestine in animals from the comparison group at the same time showed the presence of a defect in the muscle layer with fragments of granuloma formed around the suture material. Filaments, multinucleated giant cells of a foreign body, epithelioid cells, mature dense connective tissue, and coarse collagen fibers were visualized in the samples. Also, in the samples of the intestine near the site of the defect, one can see the absence of complete restoration of the mucous-producing function of the glandular epithelium at the border with the site of damage, as evidenced by the uneven staining of vacuoles with mucin, a decrease in their number. These results indicate the advantage of proliferative inflammation processes with the formation of formed granulomas, foreign bodies around the surgical suture material. Morphological signs are characteristic of the surgical recurrent course of the inflammatory process in the intestinal wall, which was additionally provoked and supported by suture material. The use of the technique of nodular suturing of the intestinal wall defect in the experiment led to uneven germination of connective tissue around the suture material with foci of pronounced productive inflammation.
 Immunohistological studies have shown that the use of a collagen-fibrin adhesive composition minimizes the inflammatory reaction in the intestinal wall, accelerates regeneration processes and contributes to the anatomical restoration of the integrity of all layers in the defect zone. The postoperative results showed that among the patients of the main group, after three months of surgery, the recurrence of the perrectal fistula occurred in 1 patient with a collagen-fibrin adhesive composition (1.6%) concomitant type 2 diabetes mellitus. Among the patients of the comparison group, 5 patients (8.3%) had recurrent-prolonged wound infection.
 The introduction of a collagen-fibrin adhesive composition into the surgical treatment of pararectal fistulas increases the effect of treatment, namely, a decrease in the recurrence rate of 1.6% versus 8.3% in the comparison group.

Skin photoaging in young men: A clinical study by skin imaging techniques.

Differences in skin physiology and lifestyle among people can influence the skin damage caused by solar radiation. Photoprotection habits play an important role to prevent skin photoaging. Thus, the objective of the present study was to evaluate the skin changes resulting from solar exposure in young men by skin imaging techniques. Twenty-three male, aged 18-28years, with and without photoprotection habits participated in the study. Instrumental measurements in terms of dermis thickness and echogenicity (20mHz ultrasound - DermaScanC® ), morphological and structural skin characterization (Reflectance Confocal Microscopy - VivaScope® 1500) and high-resolution imaging (Visioface® ) were performed in the malar region of the face. Pigmentation disorders, telangiectasia, wrinkles and lower dermis echogenicity were observed in the skin of subjects without photoprotection habits. Reflectance Confocal Microscopy images showed an irregular honeycomb pattern (35%), polycyclic papillae (40%) and coarse collagen fibres (35%), which are related to photoaging. Sun exposure without photoprotection results in a loss of dermal echogenicity and changes in the epidermis structure and collagen fibres regardless of chronological age. Thus, the study adds data for a discussion about correct photoprotection habits among young people and can help to increase the use of sunscreens for male public.

Histopathologic evaluation of saphenous vein grafts in patients with type II diabetes mellitus undergoing coronary artery bypass grafting

IntroductionDiabetes Mellitus (DM) has been known to be a risk factor for the development of more severe form of saphenous vein graft disease after coronary artery bypass grafting (CABG). We aimed to evaluate the impact of type II-DM on histopathological features of great saphenous vein grafts of patients undergoing CABG. Patients and methodsForty consecutive patients undergoing elective CABG were enrolled into the study. Patients were grouped into two; Diabetic group (n = 20); includes patients with preoperative diagnosis of type II-DM and Nondiabetic group (n = 20): those without type II-DM. In all patients, a short segment of the great saphenous vein graft at the level of medial malleolus was taken for light microscopy and transmission electron microscopy (TEM) evaluation. Moreover, immunoexpressions of Caveolin-1, Vascular cell adhesion protein 1 (VCAM-1) and endothelial nitric oxide synthase (eNOS) were studied. ResultsThere were no differences in the demographics of patients between two groups. The magnitude of intimal fibrosis in diabetic group was slightly higher than in nondiabetics (1.95 ± 0.99 versus 1.3 ± 0.8, P = .04). In TEM, vacuolization in endothelial cells, substance accumulation along with coarse collagen fibers and cytoplasmic degeneration with vacuolization in muscle cells were detected in diabetic group. While there were no differences in Caveolin-1 and VCAM-1 immunostaining, the intensity of positive eNOS immunostaining was significantly higher in endothelium (2.10 ± 0.64 versus 1.55 ± 0.68, P = .01) and tunica media 1.75 ± 0.63 versus 1.2 ± 0.52, P = .007) in nondiabetic group, respectively) compared with diabetic group. ConclusionType II DM might be a reason for decreased expression of eNOS and increased intimal fibrosis, vacuolization of endothelial and smooth muscle cells in saphenous vein grafts. The clinical implications of these alterations on the graft patency need to be evaluated.

Eruptive Cutaneous Collagenoma: Report of Two Cases

Abstract Introduction: Eruptive cutaneous collagenoma is non familial connective tissue nevi of unknown etiology presented with an abrupt onset. To date, the literatures on eruptive cutaneous collagenoma are extremely rare in china. Here, we report two women with eruptive cutaneous collagenoma. Case present: Two women presented with multiple asymptomatic, skin-colored papules and nodules on the trunk and extremities with no systemic involvement. Histopathology revealed dense, coarse collagen fibers by hematoxylin-esoin stain and decreased, fragmented elastic fibers by Elastic stain compared with the normal skin. Basing on these findings, the diagnosis of eruptive cutaneous collagenoma was made. No specific treatment was given. Discussion: Eruptive cutaneous collagenoma is a very rare dermatosis that is often misdiagnosed as other connective tissue nevi. The pathogenesis is unclear, and also no efficient treatment is available. It is usually diagnosed based on clinical and histopathological findings. Conclusion: The present cases are relatively rare type of eruptive cutaneous collagenoma that provide more experience for clinician, and may be helpful for them to make correct diagnosis for suspicious cases.

Accuracy of tele-consultation on management decisions of lesions suspect for melanoma using reflectance confocal microscopy as a stand-alone diagnostic tool.

Diagnostic accuracy of reflectance confocal microscopy (RCM) as a stand-alone diagnostic tool for suspect skin lesions has not been extensively studied. Primary aim was to measure experts' accuracy in RCM-based management decisions. Secondary aim was to identify melanoma-specific RCM features. The study enrolled patients ≥18years that underwent biopsy of skin lesions clinically suspected to be melanoma. One hundred lesions imaged by RCM were randomly selected from 439 lesions prospectively collected at four pigmented lesion clinics. The study data set included 23 melanomas, three basal cell and two squamous cell carcinomas, 11 indeterminate melanocytic lesions and 61 benign lesions including 50 nevi. Three expert RCM evaluators were blinded to clinical or dermoscopic images, and to the final histopathological diagnosis. Evaluators independently issued a binary RCM-based management decision, 'biopsy' vs. 'observation'; these decisions were scored against histopathological diagnosis, with 'biopsy' as the correct management decision for malignant and indeterminate lesions. A subset analysis of 23 melanomas and 50 nevi with unequivocal histopathological diagnosis was performed to identify melanoma-specific RCM features. Sensitivity, specificity and diagnostic accuracy were 74%, 67% and 70% for reader 1, 46%, 84% and 69% for reader 2, and 72%, 46% and 56% for reader 3, respectively. The overall kappa for management decisions was 0.34. Readers had unanimous agreement on management for 50 of the 100 lesions. Non-specific architecture, non-visible papillae, streaming of nuclei, coarse collagen fibres and abnormal vasculature showed a significant association with melanoma in the evaluation of at least two readers. Reflectance confocal microscopy tele-consultation of especially challenging lesions, based on image review without benefit of clinical or dermoscopy images, may be associated with limited diagnostic accuracy and interobserver agreement. Architectural and stromal criteria may emerge as potentially useful and reproducible criteria for melanoma diagnosis.

Macro and Micro anatomical study of Harderian Gland of Duck and Fowl

In the present investigation, 6 numbers of each apparently healthy adult Pati duck and local fowl of Assam were utilized for detailed gross, histomorphological, histochemical and ultrastructural studies. The Harderian gland in the Patiducks and Fowl were located in the medioventral region of the orbital cavity attached along with the eye ball. The gland was not having any grossly demercablelobulation but still there was dorsally slightly narrow part whereas the ventral part was somewhat more wider. In duck, from the capsule, thin connective tissue septa penetrated into the gland and divided parenchyma it into lobes and lobules which were unequal and polygonal in shape. Each lobule contained a central lumen. From the capsule and septa thin streaks of interstitial connective tissue penetrated between the acini and tubules. The columnar epithelial cells lining the acini showed considerable variation in height depending on their functional state. The nerve fibers were also extending from the capsule inside the parenchyma along with the other connective tissue fibers. Harderian gland of Fowl was also covered with a thin connective tissue capsule and consisted of coarse collagen, fine reticular and elastic fibers, blood vessels, and nerve fibers, which were penetrating the parenchyma very frequently by forming septa and trabeculae. The glands were to be of multilobulartubulo-alveolar type and emptied into a wide lumen which was lined by columnar epithelial cells. The histochemical sections were found positive for PAS Alcian blue. The reaction for acid phosphates and alkaline phosphatase were also moderate to intense in the harderian gland. The scanning electron microphotograph of harderian gland showed the acini, secretory granules and connective tissue fibers in the duck and fowl. The secretions of the gland were accommodated inside the acini and looks like a woollen ball.

Clinical Characteristics of Connective Tissue Nevi in Tuberous Sclerosis Complex With Special Emphasis on Shagreen Patches

Patients with tuberous sclerosis complex (TSC) frequently develop collagenous connective tissue nevi. The prototypical lesion is a large shagreen patch located on the lower back, but some patients only manifest small collagenomas or have lesions elsewhere on the body. The ability to recognize these variable presentations can be important for the diagnosis of TSC. To describe the clinical characteristics of connective tissue nevi on the trunk and extremities of patients with tuberous sclerosis complex. A retrospective analysis of patient medical records and skin photography was performed; 104 adult patients with TSC were enrolled in an observational cohort study that was enriched for those with pulmonary lymphangioleiomyomatosis, and was therefore composed mostly of women (99 women, 5 men). All patients included were examined at the National Institutes of Health (NIH) in Bethesda, Maryland, from 1998 to 2013. Connective tissue nevi were categorized per anatomic location and size. Lesions less than 1 cm in diameter were termed collagenomas. Shagreen patches were characterized as small (1 to <4 cm), medium (4 to <8 cm), and large (≥8 cm). Frequency, anatomic location, size, and histological appearance of connective tissue nevi in patients with TSC. Overall, 58 of 104 patients (median [range] age, 42 [19-70] years) with TSC (56%) had at least 1 connective tissue nevus on the trunk or thighs; of these, 28 of 58 patients (48%) had a solitary lesion, and 30 of 58 patients (52%) had 2 or more lesions. Overall, 120 lesions from 55 patients were classified by size; 46 lesions (38%) were collagenomas; 39 lesions (32%) were small shagreen patches; 21 lesions (18%), medium shagreen patches; and 14 lesions (12%), large shagreen patches. The distribution of lesions was 9% (n = 11), upper back; 29% (n = 35), middle back; 51% (n = 61), lower back; and 11% (n = 13), other locations. All 26 shagreen patches that were analyzed histopathologically had coarse collagen fibers and 24 of 26 stained with Miller elastic stain had decreased elastic fibers. On immunoblot analysis, fibroblasts grown from shagreen patches expressed higher levels of phosphorylated ribosomal protein S6 than paired fibroblasts from normal-appearing skin. Tuberous sclerosis complex-related connective tissue nevi are not limited to the lower back, and occasionally present on the central or upper back, buttocks, or thighs. Elastic fibers are typically decreased. Recognition of these variable presentations can be important for TSC diagnosis.

Management of Idiopathic Gingival Enlargement.

A 25-year-old male reported to the department with a chief complaint of swollen gums since 10 years involving all the teeth. The swelling was aesthetically unpleasing and also causing difficulty in speech and mastication. Patient did not undergo any kind of dental treatment for the above problem. Patients dental, personal, medical, family histories were non-contributory. Patient was not under any anti-epileptic, anti-hypertensive, immunosuppressive medication and there was no history of fever, anorexia, weight loss, seizures, hearing loss or any physical or mental disorder. On extraoral examination the patient has incompetent lips with convex facial profile. Intraoral examination revealed generalized diffused nodular enlargement of gingiva on both buccal and lingual/palatal sides [Table/Fig-1,​,22 and ​and3].3]. Gingival enlargement score of grade III (Bokencamp 1994) [1] was given, that is enlargement covers three quarters or more of the crown. Gingiva was pink in colour with superimposed melanin pigmentation, firm and fibrous fibrous in consistency. The teeth were barely visible as enlargement extended up to incisal/occlusal third of all the teeth except 11, 21, 13 and 23. Stippling was absent and slight bleeding on probing was present with altered gingival contour. Gingival enlargement was not superimposed by any secondary inflammatory changes. [Table/Fig-1]: Labial view. [Table/Fig-2]: Mandibular arch. [Table/Fig-3]: Maxillary arch. Panoramic radiograph revealed no bone loss [Table/Fig-4]. Oclusal radiographs were not taken. Haematological investigation was done which was within normal limits. Histopathological examination revealed hyperparakeratinized stratified squamous epithelium showing pseudoepitheliomatous hyperplasia with thin elongated interconnecting retepegs [Table/Fig-5]. The underlying connective tissue showed extensive collagen consisting of coarse collagen fibres arranged in irregular fascicles [Table/Fig-6]. The fibroblasts were few with compressed blood vessels and scanty chronic inflammatory cell infiltrate. These findings were suggestive of fibrotic gingival enlargement. [Table/Fig-4]: Panoramic view. [Table/Fig-5]: Histological picture hyperparakeratinized stratified squamous epithelium showing pseudoepitheliomatous hyperplasia. Haematoxylin and Eosin stain (Original maginification x 20). [Table/Fig-6]: Histological picture showing extensive collagen consisting of coarse collagen fibres. Haematoxylin and Eosin stain (Original maginification x 20). On the basis of detailed case history and histological findings, the case was diagnosed as generalized idiopathic gingival enlargement. A treatment plan was devised for the patient Which included phase I therapy, followed by maintenance phase and phase II therapy. Adjunctive antimicrobial administration of systemic amoxicillin 500mg thrice daily and metronidazole 400mg twice daily for seven days was prescribed along with use of chlorhexidine mouthwash twice daily. The surgical phase included quadrant wise full mouth gingivectomy. Kirkl and knife was used for incisions on facial and lingual surfaces and Orban knife for interdental incisions [Table/Fig-7]. All granulation tissue was completely curetted and calculus remnants if any were scaled to make the areas clean [Table/Fig-8]. Patient was recalled after one month [Table/Fig-9] and two months [Table/Fig-10,​,1111 and ​and12].12]. Healing was satisfactory. [Table/Fig-7]: Gingivectomy done with Kirkland knife. [Table/Fig-8]: Removal of calculus remnants with curette. [Table/Fig-9]: Postoperative view of after 1 month. [Table/Fig-10]: Postoperative view of after 2 months. [Table/Fig-11]: Postoperative maxillary occlusal view after 2 months. [Table/Fig-12]: Postoperative mandibular occlusal view after 2 months.

Macroscopic and histological investigation of guanaco footpads (Lama guanicoe, Müller 1776).

The surface of guanaco footpads is characterized by hairless skin with up to 4-mm-thick stratum corneum that protects from abrasion. The horny layer is pliable and elastic, and ensures firm contact with irregular ground. It is padded with a particular structure of the subcutaneous layer, the digital cushion. The flat cushions of each of the two digits are of elongated ovate shape, each about 45-mm long, up to 20-mm wide, and 8-mm thick. The cushions are lined by a 1-2-mm-thick capsule that resembles a tunica albuginea. The capsule consists of coarse collagen fibers, with elastic fibers absent. The cushion capsule and dermis approach each other, and fuse along a line that runs parallel to the longitudinal axes of cushion and digit. Loose connective tissue rich in elastic fibers and acidic glycosaminoglycans separates dermis and cushion capsule lateral to the narrow interconnecting zone. The cushion capsule encloses cloudy yellowish, gelatinous material. Microscopy shows bundles of elastic fibers in abundant mucinous matrix. Tightly gathered elastic bundles adjoin the inner surface of the capsule. Rough cords of elastic fibers branch out from there and traverse to the opposite side. The cushion is pressed flat, and elastic fibers are stretched when bearing weight. With relief of load, elastic fibers contract and reset the cushion's shape. Contractile cells are absent. A resistant capsule and easily malleable mucinous contents establish the functioning as a gel pad. Mucinous connective tissue between elastic fiber bundles contains abundant basophilic matrix. Hyaluronan, chondroitin sulfate, and dermatan sulfate are main matrix constituents. Spindle-shaped or stellate fibroblasts contain vimentin, S100 protein, and neuron specific enolase. Moprhology, staining characteristics and synthesis activities of these cells meet the criteria to be classified as myxoid cells. The connective tissue in guanaco digital cushions represents myxoid tissue.

Familial cutaneous collagenoma: New affected family with prepubertal onset

Two siblings presented with clinical and histopathological findings of familial cutaneous collagenoma which is a rare connective tissue nevus, inherited in an autosomal-dominant pattern. A 13-year-old girl had oval-round, soft, painless papules, 5-10 mm in size and a total of 9-10 on her abdomen and flanks. Skin biopsy demonstrated dense, coarse collagen fibers in the dermis and a decrease in elastic fibers. Doppler echocardiography indicated an atrioseptal defect of the secundum type. Her 9-year-old brother was also examined; four lesions were discovered on his back but he was otherwise normal. Our cases comprise the sixth affected family to be reported in the medical published work and all lesions had appeared prepubertally.

Gardner Fibroma: A Clinicopathologic and Immunohistochemical Analysis of 45 Patients With 57 Fibromas

Gardner fibroma (GAF) is a benign soft tissue lesion with a predilection for childhood and adolescence and an association with familial adenomatous polyposis (FAP) and desmoid type fibromatosis (desmoid). We report 45 patients with GAF with clinicopathologic correlation and immunohistochemical analysis for beta-catenin and related proteins. Forty-five patients with 57 GAFs were identified from surgical pathology and consultation files. Immunohistochemistry for beta-catenin, cyclin-D1, and C-myc was performed on formalin-fixed, paraffin-embedded tissues using standard techniques in 25 GAFs from 24 patients. Information about family history, intestinal polyps, colon cancer, and soft tissue tumors was available in 23 patients. Sixty-nine percent had known FAP or adenomatous polyposis coli (APC), 22% had no history of familial polyps or soft tissue tumors, and 13% had an individual or family history of soft tissue masses and/or desmoids, with follow-up periods of 6 months to 26 years (median 3 y, mean 5 y). The age range at initial diagnosis was 2 months to 36 years. Seventy-eight percent were diagnosed in the first decade, 15% in the second decade, and 7% in the third decade. Eight patients (18%) had documented desmoids concurrently or later; 4 of these had FAP and 1 had familial desmoids. Sites of GAF included the back and paraspinal region in 61%, the head and neck in 14%, the extremities in 14%, and the chest and abdomen in 11%. All displayed a bland hypocellular proliferation of haphazardly arranged coarse collagen fibers with a bland hypocellular proliferation of inconspicuous spindle cells, small blood vessels, and a sparse mast cell infiltrate. Immunohistochemically, 64% showed nuclear reactivity for beta-catenin (9 patients with known APC, 5 without definite information about FAP). One hundred percent showed nuclear reactivity for both cyclin-D1 and C-myc. beta-catenin reactivity had no correlation with age, site, or recurrence. Two beta-catenin-negative GAFs were from FAP patients. In conclusion, GAF has a predilection for childhood and early adulthood, a strong association with FAP/APC, an association with concurrent or subsequent development of desmoids, and overexpression of beta-catenin and other proteins in the APC and Wnt pathways. The proportion of sporadic GAFs that have APC mutation remains to be determined.

Habitats and air uptake based on analysis of skin structure of two Korean bullheads,Pseudobagrus brevicorpusandP. koreanus(Pisces; Bagridae)

Abstract The skin of the Korean bullheads, Pseudobagrus brevicorpus and P. koreanus, is composed of epidermis, dermis and subcutis. The epidermis has three layers, the outermost layer, middle layer and stratum germinativum. The epidermis consists of two types of gland cells, an unicellular mucous cell of sulfomucin and a large club cell having sometimes two nuclei. The epidermis has numerous intraepithelial blood vessels in P. brevicorpus but not at all in P. koreanus. Lymphatic spaces containing lymphocytes are well developed in mainly the stratum germinativum. The dermis lacks scales and consists mostly of bundles of coarse collagen fibers. The collagen bundles are arranged in parallel to each other in the dorsum and lateral region toward the dorsum, but vertically at intervals in the abdomen and lateral region toward the abdomen. Considering this unique skin structure, the two species are likely to exercise cutaneous respiration as a dual respiratory system to overcome hypoxic conditions which frequently occurs in their habitats.

Ultrastructure of Osteoarthritic Articular Cartilage

The ultrastructure of 10 osteoarthritic femoral atricular cartilage specimens obtained from patients (52-80years) undergoing total knee replacement and 10 age-matched non-osteoarthritic cartilage specimens obtained from cadavers (51-82years) was studied. The non-osteoarthritic cartilage had chondrocytes having a secretary cell characteristic with prominent nucleus and well developed organelles. With advancing age, the chondrocytes showed cellular processes extending into surrounding matrix. The pericellular matrix showed coarse collagen fibres and a finely filamentous area. Some of the cells contained a lipid drop and electron dense glycogen particles. In the osteoarthritic cartilage most of the cells appeared normal but chondrocytes near the fibrillated surface had dilated and irregular endoplasmic reticulum. Some pinocytotic vesicles, glycogen and lipid bodies were found in most of the chondrocytes. Few apoptotic cells with condensed cytoplasm were also observed. The various cell organelles could not be identified in these apoptotic cells. Electron dense lipid deposits in the cartilage matrix as well as the intracytoplasmic glycogen deposits were much increased in the osteoarthritic cartilage as compared to the control group. Calcium deposits were also seen in between the bundles of collagen fibres. Collection of perinuclear intracytoplasmic fine filaments was present in the chondrocytes near the fibrillated areas. Cell density of the cartilage was also reduced in the osteoarthritic cartilage which is due mainly to the death of chondrocytes in situ since the remains of necrotic cells were observed in the cartilage matrix. In the areas of deep fibrillation, the proliferation of deeper chondrocytes to form abnormal multicellular clusters was seen.

Familial cutaneous collagenoma: report of an affected family

A 44‐year‐old white woman was admitted to our hospital for the investigation of many roundish, pale‐colored, nodular lesions of different sizes, ranging from a few millimeters to some centimeters, symmetrically grouped on the shoulders (Fig. 1), trunk, upper limbs, and abdomen. The lesions first appeared at 20 years of age on the upper chest around the clavicular region, and thereafter gradually increased on the trunk and upper limbs; they were completely asymptomatic, appearing on normal skin without a previous history of inflammation and/or trauma. No scarring or atrophy was evident. The smaller lesions exhibited a miliaria‐like shape, being evident in particular on stretching of the skin; the larger ones showed a firm‐elastic density, no adhesion to surrounding tissue, and deep localization in the skin. No hypopigmented macules or sebaceous adenoma‐like lesions were present. Skin biopsy of a nodular lesion from the right shoulder revealed a normal epidermis and a dermis filled with bundles of dense and coarse collagen fibers (Fig. 2). Elastic fibers appeared thin and decreased in number under Verhoeff–van Gieson stain (Fig. 3). A diagnosis of cutaneous collagenoma was proposed. Routine laboratory investigations were within the normal range. Chest and skeleton (hands, pelvis, and long bones) X‐ray, electrocardiogram, and echocardiogram showed no abnormality.Nodular papules localized on the right shoulderimageHistology of a lesion taken from the right shoulder. The picture demonstrates dense and coarse collagen bundles (hematoxylin and eosin stain; original magnification, × 200)imageElastic fibers are clearly diminished in number, thin, and fragmented (Verhoeff–van Gieson stain; original magnification, × 400)imageIn order to evaluate a possible familial cutaneous collagenoma, the 19‐year‐old son of the patient was also examined. He had a 3‐month history of numerous, asymptomatic, skin‐colored nodules, ranging from 0.5 to 2 cm, on the upper back. Skin biopsy of a nodular lesion showed the same features as observed in the mother's biopsy. Routine blood and serum tests and X‐ray examinations were within normal limits. Electrocardiogram revealed an early R‐wave transition, and echocardiogram showed a left ventricular dilation with thickened aorta; aortic steno‐insufficiency was diagnosed under cardiologic examination. The diagnosis of familial collagenoma was confirmed, and similar cutaneous lesions were found in the mother's grandmother and aunt.

Papulolinear collagenoma

Connective tissue nevi are circumscribed hamartomas of the dermal extracellular matrix. Documented connective tissue nevi of the collagen type include familial cutaneous collagenomas, shagreen patches, eruptive collagenomas, and isolated collagenomas.1Uitto J Santa Cruz D.J Eisen A.Z Connective tissue nevi of the skin.J Am Acad Dermatol. 1980; 3: 441-461Abstract Full Text PDF PubMed Scopus (208) Google Scholar During the last 10 years, we have followed a patient with a unique variant of connective tissue nevi, characterized by both papular and linear skin-colored lesions affecting the dorsal aspects of the hands and fingers. Histologic examination revealed an increase of coarse collagen fibers in the dermis and diminished elastic fibers. A 45-year-old white Brazilian woman had multiple papules and linear skin-colored plaques that involved the dorsum of the hands and fingers. The lesions were asymptomatic. No history of trauma or inflammation preceding the appearance of the lesions could be elicited. The patient's relatives were not available for evaluation. Clinical examination revealed multiple linear skin-colored lesions, ranging in size from 0.4 to 6 cm, associated with tiny papules affecting the hands and fingers of the patient (Fig 1). Histologically, both papules and linear lesions were characterized by accumulation of dense, coarse collagen fibers in the dermis. The epidermis and adnexal structures appeared normal and there were no signs of inflammation (Fig 2). Van Gieson stain demonstrated enlarged but essentially normal collagen tissue. Elastic-tissue stains revealed a paucity of elastic fibrils.Fig 2Biopsy specimen of a linear lesion on the hand. Hematoxylin-eosin stain shows normal epidermis and reticular dermis. Papillary dermis exhibits both compact and coarse collagen fibers, running parallel to the dermoepidermal junction. Preserved eccrine sudoriparous ducts can be seen surrounded by dense collagen fibers. (Original magnification ×100.)View Large Image Figure ViewerDownload (PPT) Connective tissue nevi are hamartomas consisting of the various components of the dermal connective tissue. On the basis of clinical, histologic, and genetic consideration, the connective tissue nevi can be classified into defined categories. Association with extracutaneous features or a characteristic topography allows further delineation of these disease entities and aids in establishing an accurate diagnosis.2Beylot C, Bioulot-Sage P, Doutre MS, Vendeaud-Busquet M. Les dysplasies héréditaires du tissu conjonctif. Encycl Méd Chir (Paris-France). Dermatologie 1988:12660 A10, 1-21Google Scholar, 3Uitto J Santa Cruz D.J Eisen A.Z Familial cutaneous collagenoma genetic studies on a family.Br J Dermatol. 1979; 101: 185-195Crossref PubMed Scopus (66) Google Scholar, 4Smith L.R Bernstein B.D Eruptive collagenoma.Arch Dermatol. 1978; 114: 1710-1711Crossref PubMed Scopus (26) Google Scholar We report a unique variant of connective tissue nevi of the collagen type. Morphologically, slightly elevated skin-colored papules vary in size from 0.1 to 0.5 cm in diameter and elevated, well-demarcated, asymptomatic linear lesions extend up to 6 cm. The lesions predominated on the dorsum of the hands and fingers. Associated abnormalities were absent. Clinically, the lesions closely resembled scars. The patient emphatically denied any history of trauma or inflammation preceding the onset of the disorder. Histologic examination revealed a normal epidermis associated with an accumulation of dense, coarse collagen fibers in the dermis and diminished elastic fibers, characterizing an hamartomatous proliferation of the collagen.5Nogues I Le Gall F Chevrant-Breton J A hardened patch on the thigh. Conjuntival nevus of the collagen type which is also called conjunctival nevus of the fibromatous type, collagenoma, collagen hamartoma or fibromatous hamartoma.Ann Pathol. 1995; 15: 69-70PubMed Google Scholar, 6Rocha G Winkelman R.K Connective tissue nevus.Arch Dermatol. 1962; 85: 727-729Google Scholar In scars, the normal collagen bundles are replaced by fibrillary collagen. The epidermis is usually thin with a diminished pattern of epidermal rete ridges. In scars, a decreased number of adnexal epithelial structures can usually be observed. In summary, we believe our case represents a variant of connective tissue nevi of the collagen type and further suggest the designation papulolinear collagenoma. Additional cases will certainly help to classify best this unusual disorder of the collagen tissue. We thank Henry W. Randle, MD, PhD, Mayo Clinic, Jacksonville, for his assistance.

Bones in the heart skeleton of the otter (Lutra lutra).

In most mammalian species the cardiac skeleton is composed of coarse collagen fibres, fibrocartilage, and pieces of hyaline cartilage. Bone, the os cordis, is a regular constituent of the ruminant heart. The cardiac skeleton of the otter (Lutra lutra) has not previously been described. The skeleton in 30 otter hearts was studied by x-ray analysis and light microscopy. Serial sections were cut parallel to the atrioventricular plane and histochemical staining methods were performed to identify connective tissue fibres, glycosaminoglycans, mineral deposits, and bone. Age and sex of the animals under investigation were considered. The otter heart skeleton was composed of coarse collagen fibres with intercalated pieces of fibrous and/or hyaline cartilage, calcified cartilage, and lamellar bone with red or white marrow. Pieces of hyaline cartilage were not clearly defined: a perichondrial layer was missing and coarse connective tissue continuously transformed into fibrous and hyaline cartilage. In both sexes the amount of cartilage and bone were found to increase with age. Our results establish the presence of bony material in the heart skeleton of the otter, a small mammalian species. This finding indicates that differentiation of bone is not exclusively related to the size of the organ. Increasing amounts of calcified cartilage and bone correlated with increasing age.

STRUCTURAL BIOLOGY OF THE FIBRES OF THE COLLAGENOUS AND ELASTIC SYSTEMS

The different types of fibres of the collagenous and elastic systems can be demonstrated specifically in tissue sections by comparing the typical ultrastructural picture of each of the fibre types with studies using selective staining techniques for light microscopy. A practical modus operandi, which includes the recommended staining procedures and interpretation of the results, is presented. Micrographs and tables are provided to summarize the differential procedures. Reticulin fibres display a distinct argyrophilia when studied by means of silver impregnation techniques, and show up as a thin meshwork of weakly birefringent, greenish fibres when examined with the aid of the Picrosirius-polarization method. In addition, electron-microscopic studies showed that reticulin fibres are composed of a small number of thin collagen fibrils, contrasting with the very many thicker fibrils that could be localized ultrastructurally to the sites where non-argyrophilic, coarse collagen fibres had been characterized by the histochemical methods used. The three different fibre types of the elastic system belong to a continuous series: oxytalan–elaunin–elastic (all of the fibre types comprising collections of microfibrils with, in the given sequence, increasing amounts of elastin). The three distinct types of elastic system fibres have different staining characteristics and ultrastructural patterns. Ultrastructurally, a characteristic elastic fibre consists of two morphologically different components: a centrally located solid cylinder of amorphous and homogeneous elastin surrounded by tubular microfibrils. An oxytalan fibre is composed of a bundle of microfibrils, identical to the elastic fibre microfibrils, without amorphous material. In elaunin fibres, dispersed amorphous material (elastin) is intermingled among the microfibrils.

Morphology, histochemistry, and differentiation of the cat's epiglottic cartilage: a supporting organ composed of elastic cartilage, fibrous cartilage, myxoid tissue, and fat tissue.

In carnivores, the supporting organ of the epiglottis is usually called "epiglottic cartilage" (EC) although it is composed of elastic cartilage and unilocular fat storing cells. We studied the cat's EC in order to decide whether these fat storing cells are true adipocytes or fat storing (dedifferentiated) chondrocytes. ECs were studied in cat embryos at gestation days 40 and 60, in newborn, postnatal, and adult cats. We used classical staining methods, immunohistochemistry, and transmission electron microscopy to identify the different kinds of tissues contributing to the EC and to follow their differentiation. The cat's EC was defined by a layer of coarse collagen fibers representing a tunica albuginea. This tunica covered irregularly formed and irregularly sized areas of elastic cartilage, fibrous cartilage, myxoid tissue, and lobules of unilocular fat cells. All these tissue showed regular morphology. Adipocytes were provided with continuous basal laminae and fat lobules were well supplied with capillaries. Alcianophilia of ground substance was observed in all tissue components but was strongest in elastic cartilage. Most islets of elastic cartilage adhered to the tunica albuginea of the EC at one surface and were connected to the opposite surface by coarse strands of connective tissue traversing the organ. Intercalated areas of fibrous cartilage contained fuchsinophilic collagen bundles. Myxoid tissue was characterized by stellate cells in alcianophilic ground substance with intermingled fuchsinophilic bundles. All kinds of supporting tissues combined with each other without clear demarcation. Immunohistochemistry revealed strong reactivity for S-100 of chondrocytes, myxoid cells, and fat cells. Chondrocytes and myxoid cells also stained for glial fibrillary acidic protein, neurofilament protein 200, and neuron specific enolase. During development, condensation of mesenchymal cells indicated the blastema of the EC at gestation day 40. At day 60, delicate collagen fibrils indicated the future tunica albuginea, faint alcianophilia was noted in the ground substance, and multilocular fat cells were scattered throughout the blastema. At birth, alcianophilia was moderate and multilocular fat cells were numerous. Three weeks after birth, single and grouped unilocular fat cells were seen, alcianophilia of ground substance was prominent, and former blastema cells presented as ramified myxoid cells. Eight weeks after birth, the EC primarily consisted of myxoid tissue, but the first islets of cartilage were seen in the center of myxoid areas. Unilocular fat cells already formed lobules. These results show that in the cat EC a) differentiation of adipocytes precedes differentiation of all the other tissue components, and b) differentiation of myxoid tissue precedes differentiation of cartilage. It is concluded that myxoid tissue may serve as a precursor of fibrous and elastic cartilage.